1. Field of the Invention
This invention relates to a vehicle seat which is provided with a system for facilitating relieving of fatigue of a person sitting on the vehicle seat for many hours, for example, relieving lumbago (hereinafter referred to as “fatigue relieving system”).
2. Description of the Related Art
It has been stated that fatigue of a person sitting on a vehicle seat while driving for many hours may result from a rise in pressure applied to the intervertebral disk of the person, tonus of the skeletal muscles of the person, application of load to the person's skin and skeletal muscles by application of pressure to a part of the person's body, etc.
Recently, a need has arisen in the vehicle industry for a vehicle seat that is provided with a fatigue relieving system. As one of fatigue relieving systems, there has been proposed a fatigue relieving system that includes an air-bag housed within a region of a seat back of a seat for pressure-supporting the lumbar region of a person sitting on the seat, and an air-compressor connected to the air-bag. This fatigue relieving system is disclosed in Japanese Patent Application Laid-Open No. Hei. 7-313293.
In the conventional fatigue relieving system, supporting pressure applied to the lumbar region of the person sitting on the seat is adapted to be controlled by adjusting an internal pressure in the air-bag, whereby fatigue of the person is relieved. The internal pressure of the air-bag is adjusted by the supply of air to the air-bag and suction of air from the air-bag. The supply and suction of air is adapted to be performed by actuating a normally open point-of-contact switch for the air-compressor that is of an autoclear-type.
In the conventional fatigue relieving system, unless the person feels fatigued, the normally open point-of-contact switch may not be actuated by the person. Therefore, with the fatigue relieving system, it is hard to previously and effectively relieve the person's fatigue. Furthermore, it is hard to effectively relieve fatigue of the person with the air-bag installed within the seat back.
Given the foregoing, it would be desirable to provide a fatigue relieving system that can previously and effectively relieve fatigue of a person sitting on a vehicle seat.